If you liked the Jubei-chan: The Ninja Girl anime, the Anime-Planet community thinks you'd like:
Twenty year-old Mikiko Oguro (known as Kuromi to her co-workers) has just entered the dream job of a lifetime -- animation! However, upon her arrival to the famed Studio Petit, Kuromi is in for a surprise: her predecessor just quit, leaving her with the project, and the seemingly unattainable deadline! Now, with only a week left until the key animation is due, Kuromi must wrangle up the group of slackers who must finish Time's Journey 2 before it's too late!
For Niwa Daisuke, turning 14 should be accompanied by romance and the promise of new adventures into adulthood, but instead comes with a surprising revelation: all male children of the Niwa's bloodline inherit the powers (alter ego) of Dark, a phantom thief, upon their 14th birthday! Now, in addition to his ever-present quest to win the heart of his childhood friend Risa, Daisuke must commit acts of thievery (with his doppelganger Dark controlling his body), to steal mysterious pieces of art for unknown purposes. For Daisuke, his growing pains are just beginning!
Although the plotlines and settings are quite different, the theme of two beings sharing a body are present in both animes, although much more so in DNAngel. Both series contain character transformations, and a reluctant protagionist.
Naota Nanbada is a boring young boy who leads a boring life in a boring town. His older brother has left for America, and the closest he comes to any excitement is when his deadbeat dad has too much sake. But things change one day when a bizarre girl zooms up to him on a scooter and smacks him in the face with her guitar. What's more, once Naoto returns home he discovers that this strange woman has arrived ahead of him and moved in! Not only does she constantly engage in perverted activities with Naota's father and flirt with the young man himself, but she also claims to be an alien who is searching for the ‘Pirate King.' Now, Naota must learn to live with this new intruder, deal with an odd government agent who sports exceptionally large eyebrows and the mysterious Medical Mechanica, and come to terms with the fact that there are a variety of robots and weapons emerging out of his head - amongst other things. Perhaps boring wasn't so bad after all...
Naruto Uzumaki is a young ninja who bears a great power hidden inside him, a power that has isolated him from the rest of his village. As such, his only dream is to become the Hokage - the most powerful ninja, and leader of the village; but first he needs to graduate! With his inability to perform even the most basic ninja techniques, it seems that all Naruto has going for him is his determination to succeed no matter what. Teamed up with the genius Sasuke, book-smart Sakura, and their team leader Kakashi, Naruto embarks on his quest to become the Hokage. But with outside forces posing a threat to the entire Hidden Leaf village, Naruto discovers that he must become much stronger if he ever wants to realize his dream and protect the friendships he's forged.
Ranma, raised to be a man among men, has a bit of a problem: he is half woman! While training in China he fell into a strange magic spring at Jusenkyo. Now, he is eternally cursed to change into a beautiful woman whenever he is hit by cold water, but that may be the least of his problems; his father has betrothed him to marry! There's never a dull day for Ranma as he attempts to find a cure for his curse, train to become stronger, and grapple with the fact that half of himself may be more feminine than his fiancée!